Different metal elements have different reactivities. For example, potassium is very reactive and reacts vigorously with water - whereas gold is very unreactive and will not react with water, even if it is heated strongly. A reactivity series is a list of elements with the most reactive at the top and least reactive at the bottom. To the right is a reactivity series commonly used in GCSE exams.
Chemists use the reactivity series to predict what will happen in a type of chemical reaction called a displacement reaction. These reactions are involved in the extraction of many metals from their ores.
Carbon and hydrogen are often included in the reactivity
series even though they are non-metals. Carbon is included because this
helps to explain what happens in the extraction of iron in a blast furnace.
Hydrogen is included because any metal below it will not react with dilute
[ This page has been adapted from www.bbc.co.uk/schools/gcsebitesize/science